// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_QUIC_NETWORK_CONNECTION_H_
#define NET_QUIC_NETWORK_CONNECTION_H_

#include "base/macros.h"
#include "net/base/net_export.h"
#include "net/base/network_change_notifier.h"

namespace net {

namespace test {
    class NetworkConnectionPeer;
} // namespace test

// This class returns the current network's connection description. It also
// cache's the connection description to fix crbug.com/422516.
class NET_EXPORT NetworkConnection
    : public NetworkChangeNotifier::IPAddressObserver,
      public NetworkChangeNotifier::ConnectionTypeObserver {
public:
    NetworkConnection();
    ~NetworkConnection() override { }

    // Return a string equivalent of current connection type. Callers don't need
    // to make a copy of the returned C-string value. If the connection type is
    // CONNECTION_WIFI, then we'll tease out some details when we are on WiFi, and
    // hopefully leave only ethernet (with no WiFi available) in the
    // CONNECTION_UNKNOWN category.  This *might* err if there is both ethernet,
    // as well as WiFi, where WiFi was not being used that much. Most platforms
    // don't distinguish Wifi vs Etherenet, and call everything CONNECTION_UNKNOWN
    // :-(. Fo non CONNECTIION_WIFI, this returns the C-string returned by
    // NetworkChangeNotifier::ConnectionTypeToString.
    const char* GetDescription();

    // It clears the cached connection_type_ and connection_description_.
    void Clear();

    // NetworkChangeNotifier::IPAddressObserver methods:
    void OnIPAddressChanged() override;

    // NetworkChangeNotifier::ConnectionTypeObserver methods:
    void OnConnectionTypeChanged(
        NetworkChangeNotifier::ConnectionType type) override;

private:
    friend class test::NetworkConnectionPeer;

    // Cache the connection_type and the connection description string to avoid
    // calling expensive GetWifiPHYLayerProtocol() function.
    NetworkChangeNotifier::ConnectionType connection_type_;
    const char* connection_description_;

    DISALLOW_COPY_AND_ASSIGN(NetworkConnection);
};

} // namespace net

#endif // NET_QUIC_NETWORK_CONNECTION_H_
